Gun-rights advocates are right that violent films encourage school shootings. They’re wrong about how.

... Today’s gun-laden movies can trace their roots to the films of the late 1960s and early ’70s, when already violent westerns and crime dramas gave way to a darker brand of American cinema. In 1967, “Bonnie and Clyde” featured a bullet-riddled ending unlike anything moviegoers had seen before. A year later the movie “Targets” followed a mentally ill sniper on a killing rampage. And 1971’s “Dirty Harry,” followed a detective literally renowned for the size of his … revolver.

In the 1980s, the grit and counternarrative of the ’70s gave way to mega-action flicks inspired by the fallout from Vietnam, the end of the Cold War and the early days of the war on terrorism. “First Blood” (1982) and its sequels feature a former Medal of Honor recipient using a succession of increasingly large machine guns with a seemingly endless supply of ammunition. Movies like “Terminator” (1984), “Predator” (1987) and “Die Hard” (1988) all scored major box office success by employing the same model: big muscles, big guns, big explosions.

Yet for all the blood and gore featured in these movies, mass school shootings did not plague the 1960s, 1970s, 1980s or even most of the 1990s. They are a relatively recent problem, largely beginning after the 1999 massacre at Columbine High School in Littleton, Colo., that left 15 dead and 21 wounded.

In the years since Columbine, mass school shootings have become a sad, but regular, part of the American experience. The country has suffered through nearly as many mass school shootings — defined as assaults with at least four fatalities or eight nonfatal casualties — as it did in the previous 107 years. Low points include Santana High School in 2001, Virginia Tech in 2007, Sandy Hook in 2012, Umpqua Community College in 2015 and, most recently, Parkland, Fla.

The historical gap between the bloody turn in movie theaters and the epidemic of mass school shootings reveals that while violence in movies might constitute an easy target for gun rights groups hoping to place blame elsewhere, the timing for cause-and-effect simply doesn’t add up.

For a historian of violence and film, and an avid hunter (a.k.a., a gun owner), even more frustrating is the cause-and-effect that does exist, but is habitually covered up when these groups blame school shootings on Tinseltown. While Hollywood is often derided as a haven for leftists, the origins of contemporary American gun culture date to the western films of the 1950s and ’60s — films that were hardly a bastion of liberal permissiveness. ...